An easy answer is that the infrastructure that makes Google’s video empire possible (and all youtube’s video content partners), is not free as in beer or information. All the bandwidth used for watching high school kids ghost ride their parents cars, the server and datacenter infrastructure, video storage (think billions of GB of storage), transcoding (think millions and millions of hours of transcoding), and related video services has always required Google to have a revenue stream from YouTube besides “advertising” which they haven’t built out. I remember talking about this in 2007: how can youtube possibly sustain itself? Well, it doesn’t need to.